A U.S. Senator, who recently lost a powerful committee chairmanship amid a corruption scandal, leads the Senate in using “private bills” to keep illegal immigrants in her district from being deported.

Democrat Dianne Feinstein, a member of the Senate Judiciary Committee, is the lawmaker who most abuses the rarely used method to block the deportations of illegal aliens in her northern California district. Private bills are seldom introduced because, unlike public bills, they only benefit specified individuals and are therefore viewed as special treatment susceptible to fraud.

Feinstein, a former San Francisco mayor elected to the U.S. Senate in 1992, has introduced 40% of this year’s private bills, according to a news report that highlights several of the illegal aliens that the senator has helped evade deportation. The most recent is a Philippine woman ordered to leave the country after two decades. Feinstein intervened after federal courts denied the woman’s request for asylum.

The senator has also helped a deported family of Egyptians that overstayed its U.S. tourist visa by more than a decade, a Mexican family that has lived in her district illegally for 20 years and an Asian couple that entered the country more than 25 years ago as tourists and never left. Feinstein claims her private bills help families or individuals, like these, who face “exceptional” circumstances because they would encounter “enormous hardship” if sent back to their home countries.

Feinstein, who is among the wealthiest members of Congress with a net worth of $42.6 million, is no stranger to scandal. A few months ago she was forced to resign as chair of a powerful military construction committee after reports that for years she abused her position to award her husband’s companies billions of dollars in government contracts.

A few years ago Feinstein introduced a delusional law to give 1.5 million illegal immigrant farm workers and their relatives United States citizenship by granting them immediate legal residency. Feinstein and several lawmakers who joined her in the failed bid claimed the measure was necessary to provide a labor pool for the country’s multi billion-dollar agriculture industry.